1. Technical Field
The present invention relates to a robot apparatus, a position detecting device, a position detecting program, and a position detecting method.
2. Related Art
In a manufacturing process for an electronic apparatus, most of work in assembly is automated. In this automated manufacturing line, for example, an assembly robot grips and conveys objects such as a single component and an assembly component and assembles an electronic apparatus according to visual feedback control based on a picked-up image picked up by an image pickup device. In this automatic assembly by the visual feedback control, for example, when an object is a precision component or a component having a fine shape, in some case, it is necessary to detect the object at accuracy higher than position detection accuracy determined by pixel resolution indicating the performance of the resolution of the image pickup device.
In the past, a sub-pixel estimation technique is known as a technique for detecting the position of an object at accuracy higher than position accuracy determined by the pixel resolution of an image pickup device. For example, there is known a method of estimating the position of an object at a sub-pixel level by fitting-interpolating a coincidence evaluation value calculated at a pixel level (see, for example, Masao Shimizu and Masatoshi Okutomi, “Meaning and Characteristics of sub-pixel estimation in matching of images”, The Institute of Electronics, Information and Communication Engineers Transaction D-II, December 2002, Vol. J85-D-II, No. 12, pp. 1791-1800 (Non-Patent Document 1).
However, since the method is estimation based on the coincidence evaluation value calculated at the pixel level, an error due to the estimation occurs. As the pixel resolution falls, the estimation error increase and a position error also increases.